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Warragamba Dam

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93-474: Warragamba Dam is a heritage-listed dam in the outer South Western Sydney suburb of Warragamba , Wollondilly Shire in New South Wales , Australia. It is a concrete gravity dam , which creates Lake Burragorang , the primary reservoir for water supply for the city of Sydney . The dam wall is located approximately 65 kilometres (40 mi) W of Sydney central business district , 4½ km SW of

186-586: A 132 kV transmission line to a Penrith Substation. Water levels very rarely became high enough to allow operation of the generators. By 2001, it was rarely used and was disconnected from the electricity grid. In 2006, the Warragamba Deep Water Storage Recovery Project, part of the Metropolitan Water Plan, penetrated the base of the dam wall to allow the previously inaccessible lowest water in

279-401: A balancing compression stress in the downstream face, providing additional economy. For this type of dam, it is essential to have an impervious foundation with high bearing strength. Permeable foundations have a greater likelihood of generating uplift pressures under the dam. Uplift pressures are hydrostatic pressures caused by the water pressure of the reservoir pushing up against the bottom of

372-408: A continuation of the crest profile. All gates open automatically as the dam passes full water level, or can be manually opened. The auxiliary spillway is normally closed by a series of fuse plugs that are designed to be washed away in the event of an extreme flood event. As originally designed, the dam could safely withstand a peak inflow of 500,000 cubic feet per second (14,000 m/s), leading to

465-544: A dam as "jurisdictional" or "non-jurisdictional" varies by location. In the United States, each state defines what constitutes a non-jurisdictional dam. In the state of Colorado a non-jurisdictional dam is defined as a dam creating a reservoir with a capacity of 100 acre-feet or less and a surface area of 20 acres or less and with a height measured as defined in Rules 4.2.5.1. and 4.2.19 of 10 feet or less. In contrast,

558-659: A dam on the Warragamba River and followed it up in 1918 with more detailed plans. His proposals were passed onto the newly formed Metropolitan Water and Sewerage and Drainage Board in 1925 when it took over from the P.W.D. The completion of the Warragamba Emergency Scheme required during its peak 1,000 waged employees at the Headworks, and a further 1,000 on the Pipeline. All buildings used in

651-499: A dam that directed waterflow. It was finished in 251 BC. A large earthen dam, made by Sunshu Ao , the prime minister of Chu (state) , flooded a valley in modern-day northern Anhui Province that created an enormous irrigation reservoir (100 km (62 mi) in circumference), a reservoir that is still present today. Roman dam construction was characterized by "the Romans' ability to plan and organize engineering construction on

744-493: A distinct vertical curvature to it as well lending it the vague appearance of a concave lens as viewed from downstream. The multiple-arch dam consists of a number of single-arch dams with concrete buttresses as the supporting abutments, as for example the Daniel-Johnson Dam , Québec, Canada. The multiple-arch dam does not require as many buttresses as the hollow gravity type but requires a good rock foundation because

837-478: A grand scale." Roman planners introduced the then-novel concept of large reservoir dams which could secure a permanent water supply for urban settlements over the dry season. Their pioneering use of water-proof hydraulic mortar and particularly Roman concrete allowed for much larger dam structures than previously built, such as the Lake Homs Dam , possibly the largest water barrier to that date, and

930-511: A minor tributary of the Nieuwe Maas . The central square of Amsterdam, covering the original site of the 800-year-old dam, still carries the name Dam Square . The Romans were the first to build arch dams , where the reaction forces from the abutment stabilizes the structure from the external hydrostatic pressure , but it was only in the 19th century that the engineering skills and construction materials available were capable of building

1023-509: A notable increase in interest in SHPs. Couto and Olden (2018) conducted a global study and found 82,891 small hydropower plants (SHPs) operating or under construction. Technical definitions of SHPs, such as their maximum generation capacity, dam height, reservoir area, etc., vary by country. A dam is non-jurisdictional when its size (usually "small") excludes it from being subject to certain legal regulations. The technical criteria for categorising

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1116-553: A peak discharge of 354,000 cubic feet per second (10,000 m/s) down the spillway. Following a 1987 and 1989 re-evaluation of the potential rainfall and flood risks, the New South Wales Government authorised for the dam wall to be raised by 5 metres (16 ft) and constructed an auxiliary spillway on the east bank of the dam. There was also a hydroelectric power station at the dam that could generate 50 megawatts (67,000 hp), transmitting its output over

1209-649: A profession based on a rigorously applied scientific theoretical framework. This new emphasis was centered around the engineering faculties of universities in France and in the United Kingdom. William John Macquorn Rankine at the University of Glasgow pioneered the theoretical understanding of dam structures in his 1857 paper On the Stability of Loose Earth . Rankine theory provided a good understanding of

1302-566: A settling pond, and a 1,000 m (3,300 ft) canal to a distribution tank. These works were not finished until 325 AD when the dam permitted the irrigation of 25,000 acres (100 km ). Eflatun Pınar is a Hittite dam and spring temple near Konya , Turkey. It is thought to date from the Hittite empire between the 15th and 13th centuries BC. The Kallanai is constructed of unhewn stone, over 300 m (980 ft) long, 4.5 m (15 ft) high and 20 m (66 ft) wide, across

1395-408: A whole dam itself, that dam also would be held in place by gravity, i.e., there is no tension in the upstream face of the dam holding the top of the dam down. The designer does this because it is usually more practical to make a dam of material essentially just piled up than to make the material stick together against vertical tension. The shape that prevents tension in the upstream face also eliminates

1488-475: A year previously. During a days long severe weather event , affecting much of New South Wales, it overflowed for the first time since 2016 on 20 March 2021. In March 2022, following heavy rains across NSW and Queensland, the dam once again overflowed, flooding areas downstream. Warragamba Dam again reached 100% capacity on 26 November 2021 and began spilling following a prolonged period of rain in NSW. Warragamba Dam

1581-404: Is 9,051 square kilometres (3,495 sq mi). The areas closest to the lake, making up around 30% of the total catchment, are restricted access special areas. Most of the rest Although the engineers did not design Warragamba Dam as a flood control measure, it can mitigate flooding by holding floodwaters back while the reservoir fills. There have been times when drought has seriously depleted

1674-474: Is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation , human consumption , industrial use , aquaculture , and navigability . Hydropower is often used in conjunction with dams to generate electricity. A dam can also be used to collect or store water which can be evenly distributed between locations. Dams generally serve

1767-403: Is based on the fact that up to 134,000 people live and work on the floodplain, and urban growth could greatly increase this number in decades to come; giving the dam a greater capacity would enable holding back floodwaters before releasing it in a controlled fashion, reducing the need for urgent evacuations. However, there are concerns for the more than 50 recognised Aboriginal heritage sites in

1860-424: Is dependent on the strength of the side wall abutments, hence not only should the arch be well seated on the side walls but also the character of the rock should be carefully inspected. Two types of single-arch dams are in use, namely the constant-angle and the constant-radius dam. The constant-radius type employs the same face radius at all elevations of the dam, which means that as the channel grows narrower towards

1953-509: Is fed by a catchment area of 9,051 square kilometres (3,495 sq mi). The surface area of the lake covers 75 square kilometres (29 sq mi) of the now-flooded Burragorang Valley . It was designed and built by the Metropolitan Water Sewerage and Drainage Board . A small hydroelectric power station was incorporated into the design of the dam but has been disconnected from the grid since 2001. The property

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2046-602: Is owned by WaterNSW , an agency of the Government of New South Wales . The dam was added to the New South Wales State Heritage Register on 18 November 1999. Drought has severely depleted the level of the dam at times: on 8 February 2007 it recorded an all-time low of 32.55555555% of capacity. On 2 March 2012, it overflowed for the first time in fourteen years. It overflowed again in 2016, March 2021, March 2022 and April 2024. One of

2139-471: Is sloped the distribution is more complicated. The normal component of the weight of the arch ring may be taken by the arch action, while the normal hydrostatic pressure will be distributed as described above. For this type of dam, firm reliable supports at the abutments (either buttress or canyon side wall) are more important. The most desirable place for an arch dam is a narrow canyon with steep side walls composed of sound rock. The safety of an arch dam

2232-521: Is so large that engineers had to use two techniques to prevent the temperature from becoming too hot as the concrete set. One was to add ice to the wet concrete, the first application of this technique in Australia. The other was to embed cooling pipes into the concrete and circulate chilled water through the pipes. As a result, the dam wall was cooled in a few months instead of the estimated 100 years it would have taken to cool naturally. The dam impounds

2325-399: Is the more widely used of the two, though the hollow dam is frequently more economical to construct. Grand Coulee Dam is a solid gravity dam and Braddock Locks & Dam is a hollow gravity dam. A gravity dam can be combined with an arch dam into an arch-gravity dam for areas with massive amounts of water flow but less material available for a pure gravity dam. The inward compression of

2418-590: Is the thinnest arch dam in the world and one of the oldest arch dams in Asia. It was constructed some 700 years ago in Tabas county , South Khorasan Province , Iran . It stands 60 meters tall, and in crest is a one meter width. Some historians believe the dam was built by Shāh Abbās I, whereas others believe that he repaired it. In the Netherlands , a low-lying country, dams were often built to block rivers to regulate

2511-526: The Coxs , Kowmung , Nattai , Wingecarribee , Wollondilly , and Warragamba rivers, within the Hawkesbury - Nepean catchment. The dam created capacity for a reservoir of 2,027 gigalitres (4.46 × 10 imp gal; 5.35 × 10 US gal) and is fed by a catchment area of 9,051 square kilometres (3,495 sq mi). The surface area of the lake covers 75 square kilometres (29 sq mi) of

2604-657: The Fayum Depression to the Nile in Middle Egypt. Two dams called Ha-Uar running east–west were built to retain water during the annual flood and then release it to surrounding lands. The lake called Mer-wer or Lake Moeris covered 1,700 km (660 sq mi) and is known today as Birket Qarun. By the mid-late third millennium BC, an intricate water-management system in Dholavira in modern-day India

2697-579: The Harbaqa Dam , both in Roman Syria . The highest Roman dam was the Subiaco Dam near Rome ; its record height of 50 m (160 ft) remained unsurpassed until its accidental destruction in 1305. Roman engineers made routine use of ancient standard designs like embankment dams and masonry gravity dams. Apart from that, they displayed a high degree of inventiveness, introducing most of

2790-588: The Metropolitan Water, Sewerage and Drainage Board invited the geologist William Browne to investigate a proposed site. Browne found a more suitable site and continued as geological adviser until completion. The site was reviewed and approved by Dr John Savage , considered the pre-eminent expert in this field, and formally accepted by the Metropolitan Water, Sewerage and Drainage Board on 2 October 1946. The Board appointed Thomas Upton as

2883-645: The University of Oxford published a study of the cost of large dams – based on the largest existing dataset – documenting significant cost overruns for a majority of dams and questioning whether benefits typically offset costs for such dams. Dams can be formed by human agency, natural causes, or even by the intervention of wildlife such as beavers . Man-made dams are typically classified according to their size (height), intended purpose or structure. Based on structure and material used, dams are classified as easily created without materials, arch-gravity dams , embankment dams or masonry dams , with several subtypes. In

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2976-465: The platypus and echidna . Engineering experts have also questioned the modelling done by Infrastructure NSW. In April 2024, after the seventh flood in 18 months in northwestern Sydney, the NSW water minister Rose Jackson proposed the idea of lowering Warragamba Dam's storage and supplementing it with desalinated water to decrease flood danger in Sydney's north-west. The plan would mean a proportion of

3069-622: The "Gully", a fringe development in West Katoomba from about 1894, the Gully community stayed together for more than 60 years until dispossessed of the Gully by the then Blue Mountains Shire Council so a group of local businessmen could develop a speedway that became known as the Catalina Race Track . The Gully people kept talking about areas of land they had walked in as children – the nearby Megalong and Kanimbla Valleys and

3162-564: The 15th and 13th centuries BC. The Kallanai Dam in South India, built in the 2nd century AD, is one of the oldest water regulating structures still in use. Roman engineers built dams with advanced techniques and materials, such as hydraulic mortar and Roman concrete, which allowed for larger structures. They introduced reservoir dams, arch-gravity dams, arch dams, buttress dams, and multiple arch buttress dams. In Iran, bridge dams were used for hydropower and water-raising mechanisms. During

3255-503: The 6,000 hectares (15,000 acres) of World Heritage Area that would be flooded, parts of which were badly burnt in the 2019–2020 bushfires in Australia . The box gum grassy woodlands are home to threatened species of birds, including up to 50% of the remaining population of the critically endangered regent honeyeater , as well as koalas and greater gliders . In September 2020, the New South Wales Government

3348-544: The British began construction in 1898. The project was designed by Sir William Willcocks and involved several eminent engineers of the time, including Sir Benjamin Baker and Sir John Aird , whose firm, John Aird & Co. , was the main contractor. Capital and financing were furnished by Ernest Cassel . When initially constructed between 1899 and 1902, nothing of its scale had ever before been attempted; on completion, it

3441-552: The Burragorang Valley. They knew of the profound significance of these valleys for their parents and grandparents. Between 1867 and 1946, supporters of Strzelecki's proposal proposed various schemes before the site and design of the current dam received approval. In 1910, Ernest de Burgh , Chief Engineer for Water Supply and Sewerage, in the NSW Public Works Department prepared a proposal for

3534-520: The Colorado River is a constant-angle arch dam. A similar type is the double-curvature or thin-shell dam. Wildhorse Dam near Mountain City, Nevada , in the United States is an example of the type. This method of construction minimizes the amount of concrete necessary for construction but transmits large loads to the foundation and abutments. The appearance is similar to a single-arch dam but with

3627-680: The Colorado River. By 1997, there were an estimated 800,000 dams worldwide, with some 40,000 of them over 15 meters high. Early dam building took place in Mesopotamia and the Middle East . Dams were used to control water levels, for Mesopotamia's weather affected the Tigris and Euphrates Rivers. The earliest known dam is the Jawa Dam in Jordan , 100 kilometres (62 mi) northeast of

3720-714: The Middle Ages, dams were built in the Netherlands to regulate water levels and prevent sea intrusion. In the 19th century, large-scale arch dams were constructed around the British Empire, marking advances in dam engineering techniques. The era of large dams began with the construction of the Aswan Low Dam in Egypt in 1902. The Hoover Dam, a massive concrete arch-gravity dam, was built between 1931 and 1936 on

3813-610: The Middle East for water control. The earliest known dam is the Jawa Dam in Jordan , dating to 3,000 BC. Egyptians also built dams, such as Sadd-el-Kafara Dam for flood control. In modern-day India, Dholavira had an intricate water-management system with 16 reservoirs and dams. The Great Dam of Marib in Yemen, built between 1750 and 1700 BC, was an engineering wonder, and Eflatun Pinar, a Hittite dam and spring temple in Turkey, dates to

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3906-666: The Second World War period. It was the first stage in the storage and extraction of water from the Warragamba River, and was preliminary to the Waragamba Dam. All of the components are excellent examples of the civil engineering skills of the times; the Balance Reservoir is particularly significant because it provides a stilling pool downstream of Warragamba Dam for the purpose of flood discharge;

3999-495: The United States alone, there are approximately 2,000,000 or more "small" dams that are not included in the Army Corps of Engineers National Inventory of dams . Records of small dams are kept by state regulatory agencies and therefore information about small dams is dispersed and uneven in geographic coverage. Countries worldwide consider small hydropower plants (SHPs) important for their energy strategies, and there has been

4092-524: The World Commission on Dams also includes in the "large" category, dams which are between 5 and 15 m (16 and 49 ft) high with a reservoir capacity of more than 3 million cubic metres (2,400  acre⋅ft ). Hydropower dams can be classified as either "high-head" (greater than 30 m in height) or "low-head" (less than 30 m in height). As of 2021 , ICOLD's World Register of Dams contains 58,700 large dam records. The tallest dam in

4185-403: The arch dam, stability is obtained by a combination of arch and gravity action. If the upstream face is vertical the entire weight of the dam must be carried to the foundation by gravity, while the distribution of the normal hydrostatic pressure between vertical cantilever and arch action will depend upon the stiffness of the dam in a vertical and horizontal direction. When the upstream face

4278-666: The back of the dam through a large pipe to drive a water wheel and watermill . In the 10th century, Al-Muqaddasi described several dams in Persia. He reported that one in Ahwaz was more than 910 m (3,000 ft) long, and that it had many water-wheels raising the water into aqueducts through which it flowed into reservoirs of the city. Another one, the Band-i-Amir Dam, provided irrigation for 300 villages. Shāh Abbās Arch (Persian: طاق شاه عباس), also known as Kurit Dam ,

4371-491: The bottom of the dam the central angle subtended by the face of the dam becomes smaller. Jones Falls Dam , in Canada, is a constant radius dam. In a constant-angle dam, also known as a variable radius dam, this subtended angle is kept constant and the variation in distance between the abutments at various levels is taken care of by varying the radii. Constant-radius dams are much less common than constant-angle dams. Parker Dam on

4464-402: The buttress loads are heavy. In a gravity dam, the force that holds the dam in place against the push from the water is Earth's gravity pulling down on the mass of the dam. The water presses laterally (downstream) on the dam, tending to overturn the dam by rotating about its toe (a point at the bottom downstream side of the dam). The dam's weight counteracts that force, tending to rotate the dam

4557-501: The capital Amman . This gravity dam featured an originally 9-metre-high (30 ft) and 1 m-wide (3.3 ft) stone wall, supported by a 50 m-wide (160 ft) earthen rampart. The structure is dated to 3000 BC. However, the oldest continuously operational dam is Lake Homs Dam , built in Syria between 1319-1304 BC. The Ancient Egyptian Sadd-el-Kafara Dam at Wadi Al-Garawi, about 25 km (16 mi) south of Cairo ,

4650-589: The city. The masonry arch dam wall was designed by Lieutenant Percy Simpson who was influenced by the advances in dam engineering techniques made by the Royal Engineers in India . The dam cost £17,000 and was completed in 1856 as the first engineered dam built in Australia, and the second arch dam in the world built to mathematical specifications. The first such dam was opened two years earlier in France . It

4743-580: The colony at the time, continually applied for official ownership. Although their individual claims failed, in some kind of recognition of the significance of the designated tracts of land claimed, six Aboriginal Reserves (under the control of the NSW Aborigines Protection Board ) were formally declared in the Burragorang Valley. Even after these reserves were revoked, many of the traditional owners remained, quietly refusing to leave their traditional homelands. Finally pushed into

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4836-560: The construction of a desalination plant , at Kurnell . Heavy rains between June 2007 and February 2008 restored the dam level to around 67%. Despite this, Level 3 water restrictions remained in place until 21 June 2009. On 30 February 2012, it was reported that the dam was likely to overflow for the first time in fourteen years, due to continuing heavy rain in the region. The dam began spilling at 18:53 ( AEDT ) on 2 March 2012 and again on 20 April 2012. The dam reached full capacity on 17 August 2020, compared with it being less than half full

4929-671: The construction of the Rideau Canal in Canada near modern-day Ottawa and built a series of curved masonry dams as part of the waterway system. In particular, the Jones Falls Dam , built by John Redpath , was completed in 1832 as the largest dam in North America and an engineering marvel. In order to keep the water in control during construction, two sluices , artificial channels for conducting water, were kept open in

5022-526: The construction of the Emergency Scheme were designed for later re-use as cottages for the future maintenance and operations personnel. Some of these buildings were relocated from elsewhere. The main works office was the original police station at the Nepean Dam site. In 1940, a weir and water pumping station , known as the Warragamba Emergency Scheme, reached completion, just downstream of

5115-469: The dam by the water reduces the lateral (horizontal) force acting on the dam. Thus, the gravitational force required by the dam is lessened, i.e., the dam does not need to be so massive. This enables thinner dams and saves resources. A barrage dam is a special kind of dam that consists of a line of large gates that can be opened or closed to control the amount of water passing the dam. The gates are set between flanking piers which are responsible for supporting

5208-533: The dam was submitted by a consortium called Six Companies, Inc. Such a large concrete structure had never been built before, and some of the techniques were unproven. The torrid summer weather and the lack of facilities near the site also presented difficulties. Nevertheless, Six Companies turned over the dam to the federal government on 1 March 1936, more than two years ahead of schedule. By 1997, there were an estimated 800,000 dams worldwide, some 40,000 of them over 15 m (49 ft) high. In 2014, scholars from

5301-540: The dam's capacity would be brushed aside for flood mitigation. According to her, this will be cheaper than raising the dam's wall by 14 metres (a proposal scrapped by the Labor government in 2023). University of Sydney water expert, Professor Stuart Khan stated that the Sydney Desalination Plant can produce 90 gigalitres of water a year, which would drop 40% of the dam's capacity. The catchment area

5394-605: The dam. If large enough uplift pressures are generated there is a risk of destabilizing the concrete gravity dam. On a suitable site, a gravity dam can prove to be a better alternative to other types of dams. When built on a solid foundation, the gravity dam probably represents the best-developed example of dam building. Since the fear of flood is a strong motivator in many regions, gravity dams are built in some instances where an arch dam would have been more economical. Gravity dams are classified as "solid" or "hollow" and are generally made of either concrete or masonry. The solid form

5487-684: The dam. In March 1983, Lake Burragorang's level reached a low of 45.4% of capacity, only to reach the maximum level in the mid-1990s; as a consequence, the gates were opened (there was a significant spill in August 1998). Between 1998 and 2007 the catchment area experienced extremely low rainfall (in December 2004, the dam dropped to 38.8% of capacity, the lowest on record to date) and on 8 February 2007 it recorded an all-time low of 32.5% of capacity. The New South Wales State Government tried to reduce this risk by implementing water restrictions and commissioned

5580-407: The dam. The first was near the base of the dam on its east side. A second sluice was put in on the west side of the dam, about 20 ft (6.1 m) above the base. To make the switch from the lower to upper sluice, the outlet of Sand Lake was blocked off. Hunts Creek near the city of Parramatta , Australia , was dammed in the 1850s, to cater to the demand for water from the growing population of

5673-450: The dams' potential range and magnitude of environmental disturbances. The International Commission on Large Dams (ICOLD) defines a "large dam" as "A dam with a height of 15 m (49 ft) or greater from lowest foundation to crest or a dam between 5 m (16 ft) metres and 15 metres impounding more than 3 million cubic metres (2,400  acre⋅ft )". "Major dams" are over 150 m (490 ft) in height. The Report of

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5766-411: The engineer. The Warragamba River flows through a gorge that varies in width from 300 to 600 metres (980 to 1,970 ft), and is 100 metres (330 ft) in depth. This gorge opens at its upper end into a large valley, the Burragorang Valley. This river configuration allows for a relatively short but high dam wall, in the gorge, to impound a vast quantity of water. Dam construction began in 1948 and

5859-561: The first large-scale arch dams. Three pioneering arch dams were built around the British Empire in the early 19th century. Henry Russel of the Royal Engineers oversaw the construction of the Mir Alam dam in 1804 to supply water to the city of Hyderabad (it is still in use today). It had a height of 12 m (39 ft) and consisted of 21 arches of variable span. In the 1820s and 30s, Lieutenant-Colonel John By supervised

5952-588: The first places in the Gundungurra traditional homelands that most appealed to the Anglo-Celtic settlers were the river flats of the Burragorang Valley (now flooded under Lake Burragorang). Even before the valley was officially surveyed in 1827-1828, many early settlers were already squatting on blocks that they planned to officially occupy following the issue of freehold title grants. From the Burragorang Valley and using Aboriginal pathways, other valleys to

6045-742: The first was the Roman-built dam bridge in Dezful , which could raise water 50 cubits (c. 23 m) to supply the town. Also diversion dams were known. Milling dams were introduced which the Muslim engineers called the Pul-i-Bulaiti . The first was built at Shustar on the River Karun , Iran, and many of these were later built in other parts of the Islamic world . Water was conducted from

6138-485: The following criteria: [REDACTED] This Misplaced Pages article was originally based on Warragamba Emergency Scheme , entry number 01376 in the New South Wales State Heritage Register published by the State of New South Wales (Department of Planning and Environment) 2018 under CC-BY 4.0 licence , accessed on {{{accessdate}}}. [REDACTED] Media related to Warragamba Dam at Wikimedia Commons Dam A dam

6231-534: The force of water. A fixed-crest dam is a concrete barrier across a river. Fixed-crest dams are designed to maintain depth in the channel for navigation. They pose risks to boaters who may travel over them, as they are hard to spot from the water and create induced currents that are difficult to escape. There is variability, both worldwide and within individual countries, such as in the United States, in how dams of different sizes are categorized. Dam size influences construction, repair, and removal costs and affects

6324-431: The group of five cottages associated with the construction of the dam are considered to be of high significance because they housed the operations staff between 1940 and 1959. These have since been incorporated into the Warragamba township, one of the largest townships in the Shire of Wollondilly. The Warragamba Emergency Scheme was listed on the New South Wales State Heritage Register on 18 November 1999, having satisfied

6417-444: The main dam site, located on the east bank of the Warragamba River. Access to the site was along the road currently known as Weir Road. Major elements of the construction works still extant include the weir, a 10-cable cableway, shads, batching plants, roads, electrical substation, chlorination plant, maintenance staff accommodation, balance reservoir, Megarritys Bridge , water pumping station, tunnels, and associated pipelines. In 1943

6510-422: The main stream of the Kaveri River in Tamil Nadu , South India . The basic structure dates to the 2nd century AD and is considered one of the oldest water diversion or water regulating structures still in use. The purpose of the dam was to divert the waters of the Kaveri across the fertile delta region for irrigation via canals. Du Jiang Yan is the oldest surviving irrigation system in China that included

6603-410: The now flooded Burragorang Valley. The main spillway has five crest gates: A central drum gate with a 27 metres (89 ft) clear span with a pair of radial gates on each side. Each radial gate has a 12 metres (39 ft) clear span . The drum gate is hinged along the upstream edge to the upstream crest and lowers into the dam wall to allow water to flow over it. When it is fully open, it forms

6696-683: The other basic dam designs which had been unknown until then. These include arch-gravity dams , arch dams , buttress dams and multiple arch buttress dams , all of which were known and employed by the 2nd century AD (see List of Roman dams ). Roman workforces also were the first to build dam bridges, such as the Bridge of Valerian in Iran. In Iran , bridge dams such as the Band-e Kaisar were used to provide hydropower through water wheels , which often powered water-raising mechanisms. One of

6789-429: The other way about its toe. The designer ensures that the dam is heavy enough that the dam's weight wins that contest. In engineering terms, that is true whenever the resultant of the forces of gravity acting on the dam and water pressure on the dam acts in a line that passes upstream of the toe of the dam. The designer tries to shape the dam so if one were to consider the part of the dam above any particular height to be

6882-469: The primary purpose of retaining water, while other structures such as floodgates or levees (also known as dikes ) are used to manage or prevent water flow into specific land regions. The word dam can be traced back to Middle English , and before that, from Middle Dutch , as seen in the names of many old cities, such as Amsterdam and Rotterdam . Ancient dams were built in Mesopotamia and

6975-607: The principles behind dam design. In France, J. Augustin Tortene de Sazilly explained the mechanics of vertically faced masonry gravity dams, and Zola's dam was the first to be built on the basis of these principles. The era of large dams was initiated with the construction of the Aswan Low Dam in Egypt in 1902, a gravity masonry buttress dam on the Nile River . Following their 1882 invasion and occupation of Egypt ,

7068-424: The project reached a major milestone when it increased the available storage from 1,857 gigalitres (6.56 × 10 cu ft) to 2,027 gigalitres (7.16 × 10 cu ft). Enhancements to the dam were completed in 2009, including the addition of an auxiliary spillway to manage extreme flood events. Other recent major work includes a complete upgrade of the three passenger lifts within the dam wall, an upgrade of

7161-420: The reservoir to be available. This new outlet was below the minimum level required for gravity flow, which delivered water from the existing outlets. The project constructed a new pumping station downstream of the dam. The new pumping station is within the Emergency Scheme pumping station chamber. This project provided access to eight per cent more water or approximately six months of extra supply. On 15 April 2006,

7254-487: The state of New Mexico defines a jurisdictional dam as 25 feet or greater in height and storing more than 15 acre-feet or a dam that stores 50 acre-feet or greater and is six feet or more in height (section 72-5-32 NMSA), suggesting that dams that do not meet these requirements are non-jurisdictional. Most US dams, 2.41 million of a total of 2.5 million dams, are not under the jurisdiction of any public agency (i.e., they are non-jurisdictional), nor are they listed on

7347-498: The town of Wallacia , and 1 km NW of the village of Warragamba. The dam was devised as part of a collective engineering response to Sydney's critical water shortage during World War II and was originally known as the Warragamba Emergency Scheme . Constructed between 1948 and 1960, the dam created capacity for a reservoir of 2,031 gigalitres (4.47 × 10 imp gal; 5.37 × 10 US gal) and

7440-428: The travelling crest crane and a complete upgrade of the four water supply outlets in the valve house, which includes the replacement of the major valves. Since 2017, WaterNSW has been working on a risk-mitigation project, aimed at protecting human life and property in the floodplain catchment area in case of major flooding, primarily by raising the dam wall by up to 17 metres (56 ft). Infrastructure NSW's rationale

7533-406: The water level and to prevent the sea from entering the marshlands. Such dams often marked the beginning of a town or city because it was easy to cross the river at such a place, and often influenced Dutch place names. The present Dutch capital, Amsterdam (old name Amstelredam ), started with a dam on the river Amstel in the late 12th century, and Rotterdam began with a dam on the river Rotte ,

7626-642: The water load, and are often used to control and stabilize water flow for irrigation systems. An example of this type of dam is the now-decommissioned Red Bluff Diversion Dam on the Sacramento River near Red Bluff, California . Barrages that are built at the mouths of rivers or lagoons to prevent tidal incursions or use the tidal flow for tidal power are known as tidal barrages . Embankment dams are made of compacted earth, and are of two main types: rock-fill and earth-fill. Like concrete gravity dams, embankment dams rely on their weight to hold back

7719-427: The west were occupied and developed by the settlers with construction of outstations and stock routes. These cattle entrepreneurs were then followed by cedar-wood extractors and miners. In 1845, Paweł Strzelecki drew attention to the Warragamba River as a water supply catchment; in 1867, supporters proposed a dam. The Gundungurra traditional owners resisted the taking of their lands, and, relying on various laws of

7812-581: The world is the 305 m-high (1,001 ft) Jinping-I Dam in China . As with large dams, small dams have multiple uses, such as, but not limited to, hydropower production, flood protection, and water storage. Small dams can be particularly useful on farms to capture runoff for later use, for example, during the dry season. Small scale dams have the potential to generate benefits without displacing people as well, and small, decentralised hydroelectric dams can aid rural development in developing countries. In

7905-548: Was 102 m (335 ft) long at its base and 87 m (285 ft) wide. The structure was built around 2800 or 2600 BC as a diversion dam for flood control, but was destroyed by heavy rain during construction or shortly afterwards. During the Twelfth Dynasty in the 19th century BC, the Pharaohs Senosert III, Amenemhat III , and Amenemhat IV dug a canal 16 km (9.9 mi) long linking

7998-438: Was a popular picnic spot for Sydneysiders , but access to the public was restricted after 1999 due to A$ 240 million of upgrades in that time. It reopened to the public on 8 November 2009. Access to the dam wall and terrace gardens opened from 23 December 2012 to 28 January 2013 at weekends and public holidays. The Emergency Scheme is representative of the collective engineering response to Sydney's critical water shortage during

8091-560: Was built. The system included 16 reservoirs, dams and various channels for collecting water and storing it. One of the engineering wonders of the ancient world was the Great Dam of Marib in Yemen . Initiated sometime between 1750 and 1700 BC, it was made of packed earth – triangular in cross-section, 580 m (1,900 ft) in length and originally 4 m (13 ft) high – running between two groups of rocks on either side, to which it

8184-402: Was completed in 1960. The resulting dam of the Warragamba River formed Lake Burragorang, which is one of the largest reservoirs for urban water supply in the world. The dam wall comprises 1,612,000 cubic yards (1,232,000 m) of concrete. It was laid as interlocking blocks roughly 17 metres (56 ft) on each side, which were later grouted together to form a continuous, monolithic wall. It

8277-488: Was linked by substantial stonework. Repairs were carried out during various periods, most importantly around 750 BC, and 250 years later the dam height was increased to 7 m (23 ft). After the end of the Kingdom of Saba , the dam fell under the control of the Ḥimyarites (c. 115 BC) who undertook further improvements, creating a structure 14 m (46 ft) high, with five spillways, two masonry-reinforced sluices,

8370-461: Was ordered by the federal Department of Agriculture, Water and the Environment to re-do their Indigenous heritage work, concerned that NSW has not adequately addressed the concerns of Gundungurra and other traditional owners in their cultural heritage surveys. The federal review also said that the environmental impact assessment lacked detail on how the project could affect species such as

8463-404: Was possibly the world's first concrete arch dam. Designed by Henry Charles Stanley in 1880 with an overflow spillway and a special water outlet, it was eventually heightened to 10 m (33 ft). In the latter half of the nineteenth century, significant advances in the scientific theory of masonry dam design were made. This transformed dam design from an art based on empirical methodology to

8556-461: Was the first French arch dam of the industrial era , and it was built by François Zola in the municipality of Aix-en-Provence to improve the supply of water after the 1832 cholera outbreak devastated the area. After royal approval was granted in 1844, the dam was constructed over the following decade. Its construction was carried out on the basis of the mathematical results of scientific stress analysis. The 75-miles dam near Warwick , Australia,

8649-682: Was the largest masonry dam in the world. The Hoover Dam is a massive concrete arch-gravity dam , constructed in the Black Canyon of the Colorado River , on the border between the US states of Arizona and Nevada between 1931 and 1936 during the Great Depression . In 1928, Congress authorized the project to build a dam that would control floods, provide irrigation water and produce hydroelectric power . The winning bid to build

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